Carlsbad Caverns

Limestone caverns are among nature s most spectacular displays. These caves occur in many parts of the world. Examples are Carlsbad Caverns In New Mexico, Jeita Caves in Lebanon, the Blue Grotto in Italy, and the Jenolan Caves In Australia. Wherever they occur, the chemistry of their formation involves the aqueous equilibria of limestone, which Is calcium carbonate. Three such equilibria, linked to one another by Le Chatelier s principle, play essential roles In cave dynamics. 

The story does not end with cavern formation. Many limestone caves, such as Carlsbad Caverns, contain spectacuiar formations that inciude staiagmites, stalactites, and limestone columns. We need to examine the equiiibria more cioseiy to understand how these structures form. 

Polyak VJ, McIntosh WC, Provencio P, Giiven N (1998) Age and Origin of Carlsbad Caverns and related caves from " °Ar/ Ar of alunite. Science 279 1919-1922 Porcelli D, Swanzenski PW (2003)The behavior of U- and Th- series nuclides in groundwater. Rev Mineral Geochem 52 317-361... 

Mexican free-tailed bat, Tadarida brasiliensis 1991 liver females vs. males Carlsbad Cavern, NM May Max. 3.3 FW 1.9 FW vs. 3.5 FW 179... 

Check these official and unofficial sites for Carlsbad Caverns National Park and Mammoth Cave National Park for details on how these underground landmarks formed Ample travel information is included. 

Wilkening, M. Romero, V. (1981)222Rn and atmospheric electrical parameters in the Carlsbad caverns. Journal of Geophysical Research, 86, 9911-16. 

Paul A. Burger, Carlsbad Caverns National Park, 3225 National Parks Highway, Carlsbad, NM 88220, paul burger nps. gov. 

Folk, R.L. and Assereto, R., 1976, Comparative fabrics of length-slow and length-fast calcite and calcitized aragonite in a Holocene speleothem, Carlsbad Caverns, New Mexico, J. Sed. Petrol. 46 486-496. 

Chapman, J. B., Ingraham, N. L., and Hess, J. W., 1992, Isotopic investigation of infiltration and unsaturated zone flow processes at Carlsbad Caverns, New Mexico, J. Hydrol. 133 343-363. 

Quartz occurs in dolomite crusts in Carlsbad Cavern, Lechuguilla Cave, and probably other nearby caves, and within unusual iron oxide-rich stalactites (the Rusticles ) in Lechuguilla Cave. Most of the crystals of quartz were euhedral and 10-200 pm in diameter however some exceeded 200 pm in diameter (Fig. 3). In the Rusticles of Lechuguilla Cave, quartz crystals, along with dolomite and calcite, formed cement in the central canal of these stalactites. Within the quartz were filaments of iron-... 

Figure 3. (A B)SEM images of quMtz crystals in dolomite crust, Carlsbad Cavern (D=dolomite).

Figure 4. SEM images of filamentous aggregates of faioct ech al smectite enveloping dolomite crystals in dolomite crust (Carlsbad Cavern). Image on die right was modified from Polyak and Guven (2000). Arrows point to coated dolomite rhombs.

We are grateful to R. Turner and the Lincoln National Forest, D. Pate and J. Richards and Carlsbad Caverns National Park, and J. Goodbar and the Carlsbad District Bureau of Land Management for field assistance and permissions to collect samples. We also thank Carol A. Hill and Annabelle M. Foos for their constructive reviews of our manuscript. 

Hill, C.A., 1987, Geology of Carlsbad Cavern and other caves in the Guadalupe Mountains, New Mexico and Texas, New Mexico Bureau of Mines and Mineral Resources, Bulletin, 117 150p. 

Polyak, V.J. and Giiven, N., 2000, Authigenesis of trioctahedral smectite in magnesium carbonate speleothems in Carlsbad Cavern and other caves of the Guadalupe Mountains, New Mexico, Clays Clay Miner, 48 317-321. 

Polyak, V.J., Karlsson, H.R., and Provencio, P., 2001, Cave-authigenic dolomite in the Guadalupe Mountains, New Mexico, unpublished manuscript, Carlsbad Caverns National Park, 25p. 

Polyak, V.J. and Mosch, C.J., 1995, Metatyuyamunite from Spider Cave, Carlsbad Caverns National Park, New Mexico, NatlSpeleol Soc Bull, 57 85-90. 

Although erosion and deposition are most easily observed where solid sediment is being moved about, invisible chemical reactions also produce landforms. As water moves through the soil it becomes acidic, in part because of the addition of carbon dioxide produced by the decay of organic matter. This weak acid is able to dissolve some kinds of rock, particularly limestone, giving us spectacular underground caverns, such as the Carlsbad Caverns of New Mexico. If such caves develop near the surface they often collapse, and a landform called a sinkhole develops above the cave-ins. 

Gonzalez, L.A. Lohmann, K.C. (1988) Controls on mineralogy and composition of spelean carbonates Carlsbad Caverns, New Mexico. In James, N.P. and Choquette, P.W. (Eds) Paleokarst, New York Springer-Verlag, pp. 81-101. 

A border town with a booming Mexican population, El Paso is located at the westernmost tip of Texas, making it more the capital of southern New Mexico than of Texas. El Fhso is a good place to stop for supplies before heading to Carlsbad Caverns, Big Bend or Roswell. 

Investigations of the state of carbonate equilibrium of water which is transiting the vadose zone have not been numerous. The equilibrium COj (carbon dioxide partial pressure) and state of saturation with respect to calcite was studied by Holland et al. (1964) in Indian Echo Cave, Pennsylvania, and Luray Caverns, Virginia, and by Thrailkill (1971) in Carlsbad Caverns, New Mexico. These investigations showed that seepage water entering the cave was in equilibrium with a f cO2 much higher than that of the normal atmosphere and was often supersaturated with respect to calcite. 

Thrailkill, J., 1971. Carbonate deposition in Carlsbad Caverns. J. Geol., 79 683—695. Thrailkill, J., 1972. Carbonate chemistry of aquifer and stream water in Kentucky. J. 

You can also find unit studies in purchased packages or on the Internet—for example, Laura just finished a cyber unit on bats after her Uncle Ted brought her photos of his trip to the Carlsbad Caverns batcaves. The bat unit included vocabulary, biology, physics, drawing, geography, and research. 

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